IV 
PREFACE. 
formation of coal, when tropical reeds and conifers, lycopods, 
and Tree Ferns adorned this land, the scenery of our vegetation 
resembled that of the warmest parts of New Zealand, and of 
the islands in the same latitude. Nothing short of a visit to 
such localities could give an adequate idea of the Fern scenery 
of Ancient Britain, or exhibit the damp shaded ravines and 
gullies of sub-tropical countries in which this beautiful order 
reigns in profuse luxuriance ; where the Tree Ferns attain 
their most exalted height, and spread in drooping loveliness 
a crown of fronds from six to eighteen feet in length, from 
an erect taper stem, often exceeding twenty feet in height; 
and where the trailing species hang from stem to stem, and 
crag to crag, in festoons and fringes of the deepest green ; 
while beneath, elegant, featherlike, or broad and swordlike 
fronds form a soft cool carpet ; while every cliff is crowned 
with an overspreading mantle of maidenhair, and the very 
chinks through which the water drips and runs, are lined 
with the more minute species : even the watery marsh display- 
ing its wiry luxuriant blechna , and the dry rocky plains 
rendered cheerful and bright by the wildest profusion of brakes 
and polypodia. Coal was evidently formed by the deposit of 
the fronds and stems of tropical Ferns, and of other plants ; 
parts of the foliage, &c., being sufficiently preserved in some 
cases, to show the fruit and cellular texture of the tribes. 
It is not probable, however, that one species of that primitive 
Flora has survived; the Ferns of our times being peculiar to 
cooler regions, and attaining to less exalted stature and pro- 
fusion. 
But no less interesting are Ferns in point of Structure. They 
originate from a minute bud or bulb, which in a dust-like 
